We propose (1) to probe the mechanism by which cyclic AMP enhances motility and, indirectly, metabolism of mammalian spermatozoa; (2) to determine the role of calcium in capacitation; (3) to investigate the separate mechanisms by which glucagon, catecholamines, and vasopressin enhance gluconeogenesis; (4) to differentiate between the effects exerted at the phosphofructokinase-hexose diphosphatase sequence of reactions and those exerted on phosphoenolpyruvate carboxykinase; (5) to determine how the ferroactivator protein regulates P-enolpyruvate and the mechanism by which hormones convert an apparently inactive form of the ferroactivator to one that is capable of permitting Fe2 ion to stimulate the enzyme; and (6) to gain information on the mechanism of the reaction by which ATP is synthesized from ADP and inorganic phosphate. DTX* GGA-2557*